Why bother. Much of the time, there isn't much advantage in size for a DX over FX. For example, the 17-55 f/2.8. Moreover, it's a pro-grade lens and pros rarely shoot DX anymore. Most pro-level lenses don't have VR either in the wider lenses.

How many $1800 17-55 f/2.8 VR lenses would be sold to DX buyers? A few to DPReview members maybe, but how about the rank and file amateurs that bought their camera at Best Buy? Most buyers who consider lenses that cost over $1000 have moved to FX anyway. Those that haven't are thinking about it. Many would rather protect their investment with an FX lens, even if they aren't considering a move in short order.

Add all this to the idea that Nikon will probably offer a sub $1200 FX camera in around two years. You can already buy a D600 for $1599 refirb and they sold for around $1500 new during the past holidays if you consider the lens and rebate. $2100 with free 24-85VR. Take off $600 for the lens and there you go. What's the D7100 sell for right now? The price of moving to a better FX camera is just getting cheaper and cheaper. It's no wonder Nikon hasn't been forthcoming with DX lenses lately. Why should they?

When the entry level FX cameras start to hit, the people who said it was impossible will vanish and others will cry Nikon suckered them into DX lenses when they knew less expensive FX bodies were soon to be. I remember when this group were here on the forums saying that FX would not fall below $5000, then $2500 and now they are saying never to entry level. They quote the same old story about the sensor costing too much, which is fast becoming no longer the case.

Even the third party Sigma, Tamron and Tokina companies know what's happening. They are gearing up with more high quality FX lenses rather than more DX crop lenses. Why do you think that is? They usually try to fill vacumes left by the camera makers. If they felt there was a lot of money to be made in releasing crop lenses for the D7100, they would do so. They may still will, but I doubt many. They also see the writing on the wall.

Anyone who can't see that DX lenses are being avoided by Nikon, Canon and the 3rd party makers has their head lodged in the sand. Anyone who can't see what this means, is really deep in that same sand with their eyes closed. Doesn't that make sense? So, probably no Nikon 50-150 f/2.8 VR. Get the 70-200 f/4 instead or the 80-200 f/2.8. They are better investments. Anyone considering a D7100 ought to also consider a D600 if they can stretch the budget a little as well.